Re-Excite my generator ***UPDATE***

November 27th, 2005, 03:26 PM

Generator stopped putting out the juice, my dad said I need to re-excite it, by putting juice (6VDC) to the brush wires while it's running to jump-start the field.This naturally, scares the bejeebees outta me, any thoughts?

Hmmmm,I understand the exciter field idea. Can't say as I have ever heard of it being done manually though.What kind of generator are you talking about?Maybe some of the electrical engineers on here will help you out.AK Chappy

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When a generator sits for quite some time, the two magnets (on two poles generator) loose its residual magnetisim. Exiting the field means to polarize the magnets. To give it magnetic strength by inducing(exite) low voltage onto the field.

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Originally posted by --GQ--: When a generator sits for quite some time, the two magnets (on two poles generator) loose its residual magnetisim. Exiting the field means to polarize the magnets. To give it magnetic strength by inducing(exite) low voltage onto the field.

You gonna hold the wires for AZF GQ? Acutally makes sense as those magnets are created as opposed to being natural.

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do not do that its an altenator not a generator. it does not use the same regulation setup that the old time auto generators used. the field is set up in the stator and picked off by a set of sliprings on the rotor.if you short or attempt to polarize the altenator fields your gonna have smoke.most generators use a seperate field current to regulate output. if its a permmanant magnet style set up the mags are not connected to anything anyway as its a permmanant magnet. I would suggest a service manual and some reading on DC and AC generating teqniques.

no tech questions by PM, they wont get answered.
you have to be trusted by the people that you lie to .

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Professor rodbolt, all the GEN. setup that i came across has at least two windings ( on two poles gen.) of small guage wire on each magnet isolated from the main windings which is connected to connecting points on the GEN. set. It should be labeled "excite". The low voltage current does not travel thru the slip rings. In any case the low voltage will not damage the GEN. since the Main windings are of heavy guage wires. 6 volt is mearely an insect biting on an elephant. And the "exiting" is done prior to starting the engine. Boomyal having experienced paralling 3 phase alternators when i was in college to get my EE, I have all the confident. There are no wires to hold. Simply clip the leads from the 6v battery to the "exite" leads on the GEN. Let it sits a bit for the magnet to gain strength. On big GEN. set, the exite voltage is perminant. It is used to control the out put voltage.Then again just to be safe, each GEN. set up may differ. Refering to your GEN. manual is never a bad idea.

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AZF... Go here web page Then go to page 7. It will tell you how to excite your generator (flash the field)Another way.....Field Flashing of Portable GeneratorsThis tip comes from the Briggs & Stratton Customer Education Department. As an alternative to flashing a rotor winding with a battery applied to the brushes, an electric drill may be used. Follow these steps to flash the generator:Plug the electric drill into the generator receptacle. (Cordless drills do not work)If the drill is reversible, move the direction switch to the forward position.Start the generatorWhile depressing the trigger on the drill, spin the drill chuck in reverse direction. This will excite the field and the generator will now produce electricity. If spinning the chuck one direction does not work, try spinning the chuck in the other direction as you may have the reverse switch positioned backwards. Use caution not to get your hand or other materials caught in the chuck. As soon as the field is excited, the generator will produce power and the drill will turn on.The reason this works is because the electric motor in the drill will act as a small generator when spun backwards. The magnets in the drill's motor induce a voltage into the motor windings, which is fed back through the trigger, cord and into the generators receptacle. From there it goes into the power winding of the stator. The voltage going through the power winding creates a magnetic field, which is intensified due to the iron core of the stator laminations. The rotor intersects this magnetic field as it is spun past the power winding, thus inducing a voltage in the rotor winding. Once current flow is present in the rotor winding the rotor has been flashed.If either of these two ways do not work you have other problems.

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"Flashing the Field" was actually a button labeled flash on the generators we used in the military (I am going back almost 25 yrs). I would follow the directions that Trent listed .... who know's we could be calling you Sparky soon!

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I run alot of different power equipment off my generac on my truck. Some of it needs to have the generator "excited". For instance I have a Hilti Hammer for busting frost that will not work until I start a drill with it first. Every time I shut off the hammer I have to re start with drill. I found if I leave a battery charger "for my battery operated tools " pluged into the AC outlet of generac, I don't have to re excite each time.

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Just finished, and it worked great!Gen wouldn't start, so removed side covers, removed fuel lines, dumped old fuel, flushed lines, pulled bowl off carb, cleaned it, checked float, changed oil, reassembled, pulled cord a few times with switch off, then switched it on and it took one pull to start, and it ran like a dream. Took it out of garage, plugged in the AC drill (used the "drill" method mentioned above), and it barely took even 1/64th of a turn of the drill and WHAM! it was producing power!Ran it for quite a while, it ran great. I feel so good that I did it, and I didn't need to take it to a shop and pay $$$ for something I could do.Thanks all for the help and encouragement.

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the reason why I posted not to try it and reccomended the service manual is about a month ago I had to replace some very expensive control boards on a 2 cyl water cooled kohler cause someone tried to "Polarize" it. they used a 9v battery. fried about 400 dollars worth of stuff. when it comes to working on portable gensets you really need to know how the genset is designed. some are actually altenators and others are DC generators fed through a solid state inverter. one italian model I had the pleasure to play with used a DC generator fed through a rotary converter. wont touch one again though. for the hassle I could have bought the blowboater a new genset and come out ahead. glad to see your flash worked though if anyone ever runs into a single cyl diesel ruggerini genset from the 70's run away.

no tech questions by PM, they wont get answered.
you have to be trusted by the people that you lie to .